This project on Polyoma Virus Crystallography, which is a supplemental undertaking in our research program on Assembly of Viruses, Membranes and Tissue, is focused on computer analysis of X-ray diffraction data and on application of the Kalata TV Detector constructed in our laboratory to efficient acquisition of accurate X-ray diffraction data from crystals of polyoma capsids and virions. The goal of this study is the determination of the structure of the polyoma virion and capsid initially at 22 A resolution, then at 8 A resolution and ultimately to the highest resolution possible. These results will provide information about the organization of the viral chromatin and the mechanisms of its packaging by the capsid proteins.